New clutch setup, testing.

[mach9]

Just ran a few lengths of the field, testing new clutch setup.
New belt Ultimax.
Engages solid at 3300-3400 pulls like a mfo on hard pack.
At wto hovering at 8600 building speed and I feel will move higher with more room. Can't reach top speed, too short area.
Stopped to check over belt and sheaves.
What do you think...
What should be hotter to touch, Primary or Secondary?
Cheers

 

[mattyg1405]

the primary should be warmer to touch...


what are you testing ?
weights?
helix ?
rivets?

good luck!

 

[mike3577]

Primary sheaves

 

[mach9]

Nice.
Ya, primary and belt were warm and secondary was still cold.
Seems to work just fine.
I just wanted to throw that quiz out there before I run the hell out of it tomorrow.
Testing a few new goodies.
47/42 overdrive helix wrapped at 80.
Overdrive primary, but weights may be way off yet?
Seemed to coast nicely, but not enough ride time yet.
I'll report more soon, maybe Friday.

 

[shadow44]

Where are you gonna test Mark?

 

[mach9]

They say Haliburton is in the white zone...

 

[Beenba]

Were heading up that way for Friday by the sounds of it.
Hoping to put my 1st km on the sled since I have owned it..my front lawn is growing grass i swear.
I'd love to get a feel for this sled....

 

[UP bushman]

Primary should barely be warm at all if tuned properly even though it's on the engine almost cool especially if your trail riding. If you get the clutching right the best test is under heavy load like deep snow. Venting is key to get cool air in the clutch cover this all effexts performance and belt life. My sled under load in deep snow and climbing both clutches are almost cool to touch even though belt is warm.

 

[mach9]

Bare with me...
Ok, so I've pulled the Yamaha primary.
Wasn't happy with the grooving the hard 8DN put in the sheaves.
So I wanted to start over with softer belts and throw on something new and take some time to revive my old primary.
Heard some good things about the CVtech PB80 with guys running them on 4tec 1200's.
So why not on a Nytro. So far very nice results with just bolting it on.
No more rattle and with some tweaks this primary will do more as it goes into overdrive well.
Here is a pic.

 

[09nytro]

Keep us posted on this....

 

[shadow44]

Interesting stuff Mark

 

[mach9]

So far here is the results after a straight bolt of CVtech PB80.
New softer Ultimax belt. Engages hard at 3400 and pulls very hard at wto bouncing around 8600-8700. RPM climbs as you keep on it. On ice hitting 9100rpm. On plowed road hitting 8850 rpm. Speedo speeds showing a high of 109mph.
So between Ice and Road and breaking in a belt rpm has changed a bit.
Bit of a bear on tighter trails. So more testing to come.
Changing spring and weights.
Going for lower engagement for around 3100.
If it over revs... I'll throw some weights into it to bring down the finish RPM. Would like it to pull sooner into 9000 rpm zone on hard pack trails as I don't need to be running 110mph on roads and lakes too often, only for testing... Stay tuned.

 

[mach9]

Found some more with changes. Just hit 112mph (dream meter) on plowed road about 1 hour ago, 9200 rpm and it was still pulling.

 

[STAIN]

How does it pull compared to the Draggin-Flies?

 

[mach9]

How does it pull compared to the Draggin-Flies?

Pulls awesome compared and less belt slippage. (less belt dust)
With the Ultimax belt I had to back off the secondary tension a little so not to be so grabby.
Once I figured out that Yamaha even in stock form squeezes the belts harder than needed (due to the hard 8DN) I was on the right track.
It was a bit of a learning curve but the adjustments with springs and weights is too easy.
I think I can get more out of it yet and I heard that the Dayco XTX belt is even easier for clutches to hold.